Tube clamping means



Aprifi 25, 1950 4 FRANCK 2,595,665

TUBE CLAMPING MEANS Filed May 41, 1946 2 Sheets-Sheet JL VII/III,

G. E. FRANCK TUBE CLAMPING MEANS April 25, 1950 Z SheetS-Sheet 2 Filed May 4, 1946 Patented Apr. 25, 1950 ITED STATES TENT ()FFICE 4 Claims. (01. 29 -2s4 The invention relates to tube clamping means for use as part of a tube flaring tool or the like and has as a general object to provide clamping means of new and improved construction.

Tube clamping means for use as part of a flaring tool or the like must satisfy many requirements if it is to be completely satisfactory in all respects. A workman employing means of this character is usually an installation man or a repairman and thus carries this flaring tool in a kit along with many other tools; It is essential, therefore, that the tool be capable of being packed efficiently and in a small space and should not have such construction that, though the actual tool is not excessively large, nevertheless it takes up considerable room in the kit or wastes space because of a lateral projection or the like. All parts of the tool including the clamping means should be as light as possible. consistent of course with necessary strength and proper functioning of the tool. During the day the workman will encounter tubes of a variety of sizes and, since it would not be practical to have a different tool for each size of tube, the clamping means should be capable of clamping a number of different sized tubes.

In the past, the in line tube clamping means, that is, means having apertures for. clamping various sized tubes arranged in a longitudinal line, have proved most successful and popular. They have, however, had shortcomings which have not to date been successfully overcome. Such clamping means have consisted of parallel bars hinged at one end and drawn together at the other end after the tube to be clamped has been inserted therebetween. The result, of course, is a bending force and has either necessitated the bars being made extremely heavy or has required the formation of teeth in the recesses receiving the tubes. The result, of course, has been scoring and marking of the tubes which is undesirable from the appearance standpoint as well as from the mechanical standpoint, for frequently thatscoring or marking has been enough to weakenthe tubes.

It is among the more particularobjeots of the invention, therefore, to provide an in line, multiple-tube-sized clamping means which does not score or mark the tubes and which is of light weight construction.

A further object. is to provide an in line,

multiple-tubasized clamping means in which the clamping thrust is a longitudinal force and thus one of tension or compression as distinguished from lateral, hence bendingjor'ce Still a further object is to provide tube clamp- 2 ing means composed of a carrier, a plurality blocks recessed to form tube receiving bores and supported for movement longitudinally of. the carrier, and means for applying to the blocks a longitudinal tube clamping force.

Another object is to, provide tube clamping means which is readily disassembled so as to per;- mit removal of the blocks. from the carrier for repair and subsequent replacement or substitution.

Another object is to provide a tube clamping means of the in l ne, plural block andplural recess type in which the bores for the various sized tubes are so arranged as to permit the employment of blocks of uniform size, thus facilitating manufacture of the clamping means. g

Yet another object is to provide tube clamping means in which extruded metal bars maybeemployed and first cut into blocks of uniform length and then drilled or otherwise formed to have recesses in opposed faces of the blocks. 5

Other objects and advantages will become ap} parent from the following detailed description taken in connection with the accompanying drawings, in which: 1

Fig. 1 is a plan view partially in section of a preferred form of tube clamping means embodying my invention. g I, H

Fig. 2 is a side elevational view of the clamping means of Fig. 1. V ,r

Fig. 3 is a longitudinal sectional view taken approximately along the line 33 of Fig. 1 but with the clamping means rotated to open position, that is, from the position shown in Fig. 1.

Fig. 4 is a fragmentary sectional view taken approximately along the line 4-4 of Fig. 1.

Fig. 5 is a plan view showing thecarrier for the blocks spread to permit removal of the blocks.

Fig. 6 is a transverse sectional vi w taken aftproximately along the line 65 of Fig. l. V

Fig. '7 is a plan view similar to Fig. 1 showing a somewhat modified embbdiment of my invention.

Fig. 8 is a side elevational view, again slightly in cross section, of the clamping means of Fig. [7.

Fig. 9 is a longitudinal sectional view showing the clamping means in unclamped position.

Fig. 10 is a sectional view taken approximately along the line iii-J6 of Fig. 8. I

Fig. 11 is a transverse sectional View taken approximately along the line H-ll of Fig. '7.,

Fig. 12 is an end elevational view of onenement forming a part of the thrust applying means.

While the invention is susceptible of various modifications and alternative constructions, it is shown in the drawings and will hereinafter be described in a preferred embodiment and one modification. It is not intended, however, that the invention is to be limited thereby to the specific disclosures made. On the contrary it is intended to cover all modifications and alternative constructions falling within the spirit and scope of the invention as defined in the appended claims.

As shown in the drawings for purposes of disclosure, the tube clamping means comprises generally a carrier l of elongated form to permit of the in line arrangement of tube receiving bores or recesses, actual tube clamping or gripping means herein taking the form of a plurality of blocks l6, and means i! for applying the longitudinal force, herein a thrust, for causing the blocks to perform their tube clamping function. In both forms of the invention, the carrier or support and the blocks it are of identical construction and will, therefore, be described but once with like reference characters applied to corresponding parts in both forms of the invention. It is in the means I! for applying the clamping force to the blocks that the two forms of the invention difier and these portions will, therefore, be separately described.

Turning now to a more specific description of the invention as herein disclosed, by way of exemplary embodiment, the carrier or support [5 takes the form of a narrow, very elongated U and is preferably formed from a long strip of steel. While the strip of steel is in a proper state, it is bent into the U-shape shown in the drawings and thus has a pair of legs la and l9 which normally are parallel with one another and a base or connecting yoke forming the closed end of the U. For a purpose which will later become more apparent, the strip of steel, after it isbent into proper form, is heat treated to give the added hardness and, particularly, stiffness so that the legs l8 and I9 will be very resiliently held in parallel relationship Inasmuch as the force necessary strength to withstand any stress to which it is normally subjected. This, of course, is in contrast to the cross sectional area which the arms l8 and 19 would have to have were the 'force applied thereto a bending force. The length of the carrier 15 is determined primarily by considerations of convenience in handling by the workman, the necessity normally to provide clamping means for a given number of sizes of tubes only, and similar considerations. Unlike prior in line clamping means, increased length does not necessitate increased strength in the structure because of increased bending moment. Here the stress in the arms !8 and i9 is the same entirely independently of the length thereof.

The actual clamping of the tubes herein is effected not by the legs or arms [8 and 19 but by blocks E5 of which six are herein shown. This is, of course, an arbitrary number and might be increased or decreased without departing from the spirit and scope of the invention. Each block [6, as seen in Figs. 6 and 11, is generally rectangular in transverse section and is at each end formed with a channel 21 for the reception therein of legs I 8 and is. The blocks are slidable longitudinally of the carrier l5 and. the width of the channel 2| is for that purpose so dimensioned as to have a sliding but close fit on the edge faces of the legs l8 and IS. The depth of the channel 2!, however, is made somewhat greater than necessary so as to provide a degree of play between the blocks and the legs l8 and I9. This play serves two purposes. The first of these is to permit both'lateral shifting of the blocks and a degree of angular displacement of the blocks to make the blocks self-centering or self -aligning with respect to a tube being clamped. The other purpose or advantage is that dimensions need not be closely held and thus manuiacture is facilitated.

Not only are the blocks I6 all of the same lateral dimension, but they are also all of the same dimension longitudinally of the carrier, which dimension will herein be termed width of the blocks. This uniformity in width of the blocks is made possible despite the variation in size of the bores in which the various sized tubes are clamped by a unique positioning and relative placement of the bores in the blocks. As clearly seen in Figs. 1, 3, 6, 7, 9 and 11, the bores receiving the various sized tubes are composed of semicylindrical and complementary recesses 22 formed in abutting faces of adjacent blocks. While the recesses 22 are generally referred to as semicylindrical, they are actually very slightly out-of-round with the transverse diametrical dimension of the resulting bore a few thousandths of an inch larger than the longitudinal diametrical dimension. This prevents scoring of the tube at the lines of juncture of the two recesses.

With the exception of the end blocks which, of course, have but one recess 22 formed therein, each of the intermediate blocks has a recess formed in each side face in order that the number of blocks required may be a minimum for the number of tube sizes capable of being clamped, more specifically, so that the number of blocks need be but one greater than the number of bores. This is made possible by an association of the recesses in inverse order of their relative sizes. Thus the second block from the left in Figs. 1 and '7 has formed therein the largest and the smallest recess. The third block has formed therein the remaining smallest recess and one of the second largest recesses. The fourth block has the remaining second largest recess and one of the second smallest recesses. This arrangement is continued regardless of the number of blocks, that is, number of different sized tubes that the means is adapted to clamp.

Among the many advantages of this construction are the economy and facility with which the clamping means, particularly the blocks, may be formed. The stock from which the blocks [6 are formed will initially take the form of a bar which will be extruded to have formed therein the channels 2i and which will otherwise be of the proper dimension. This bar will then be cut to form the blocks 56 and, since all of the blocks are the same width, this cutting of the bar into the blocks is readily done automatically and there need, moreover, be no readjustment or resetting to provide blocks of different width nor any checking to see that the required number of blocks of difierent widths are provided because there is but one width of block. Thus, to the point described, the only operation that has been performed is a simple cutting-01f operation. The blocks may then be assembled either in the carrier l5 or in a suitable chucking device, the recesses 22 being formed therein in any manner such as by drilling,

broaching, or the like, and the recesses then being formed with a countersink 23 at one end, particularly if the clamping means is to be employed as part of a flaring tool. It will be readily apparent, of course, that several tiers of blocks could be chucked up and the recesses formed in all at one t me sons to reduce the cost of production. It will be understood, or course, that the clamping means is assembled simply by slipping the blocks 56 into the holder it through the open end thereof before the clampingforce exerting or generating means H is incorporated.

Turning now specifically to the form, of the invention shown in Figs. 1 to 6, the clamping force generating means ll takes theform of a screw device pivotally mounted to be. swung to a position longitudinally of the carrier l5 for applying the clamping force and to a position transversely of the carrier :5 to permit a separation of the blocks for the reception or withdrawal of. a tube. Herein the screw device comprises a T- shaped body member 26. The cross bar portion 2'? of the body member is formed at its ends with slightly reduced portions 28 forming trunnions received in apertures .19 formed in the free ends of the legs is and ill. The stem portion 3|! of the T-shaped body member 26 is tubular and is internally threaded to receive a bolt 3! having rigid therewith at its outer end a wing nut 32. The inner end of the bolt is preferably rounded and the block engaged by the end of the bolt 31 preferably has a dimple 33 formed therein for engagement by the end oi the bolt 3H. To facilitate'use of the clamping means by a workman, means is provided for arresting the: screw device in longitudinal position as it is swung toward that position preparatory to applying a tube clamping force through turning ofthe bolt 3%; To that end, a portion of the face of the and block l6 adjacent the screw device is cutaway as at at to form a lip or shoulder 35 which the end of the stem portion 39 strikes.

The construction andthe steps in the method of making the clamping means arefbelieved fully understandable from the foregoing description. While use of the clamping means will be readily apparent to any one skilled in the: art, a brief statement concerning the manner of use may not be amiss- To clamp" a piece of tube, the workman first gives the bolt 31 a few turns to disengage it from the dimple 33 and-then swings the screw device laterall to the position in Fig. 3. He next separates the blocks is at anoint depending upon the size or the tube that is to-be clamped in Fig. 3) and then inserts the tube between the separated blocks by relative movement of the tube and the clamping means: axially of the tube. Having inserted the tube, the screw device is swung to its operative or longitudinal position. As an incident to such swinging, screw device acts as a cam forcing the separated blocks togeth r into some gripping relationship to the tube. The workman need notexercise any special care in centering the tube: for, because of the play provided by the clearance between the channels 2! and the arms [3 and is, the blocks are self -centering and will automatically the tube in proper centered relationship. When the screw device is inits operative or longitudinal position, as shown in Figs. 1 and 2; the workman teeth, serrations or other means to aid in holdingthe tube against axial displacement, which means, of course, always score the tube. The workman then performs the desired operation on the tube, such as flaring the end thereof, by applying a conventional flaring. tool yoke to the clamping means. and then again gives the bolt 3i a few turns to withdraw it from the dimple. 33, swings the screw device to the position of Fig. 3 and separates the blocks clamping the tube, and withdraws the tube. Thus it. will be seen that the clamping means lends itself to very convenient manipulation by the workman, while at the sametime securely holding the tube without scor ing or marring and while yet of very light construction.

The clamping meansherein disclosed also lends itself to the substitution of different sets of blocks adapting a single carrier l5 and clamping pres sure generating means for the clamping of a great variety of tubes. This means, of course, that a workman need invest a smaller amount of money in tools and need also be burdened with a smaller weight of tools to carry around. The initial assembly of the blocks in the carrier l5 or any subsequent removal and substitution of blocks is readily efiected simply by spreading the carrier l5, as shown in Fig. 5, removing the screw device and sliding the blocks out through the open end of the carrier. Because of the resilient character of the carrier 15- and because there is no lateral force generated in a clamping operation which tends to separate the legs or arms is and I9, the screw device may be retained simply by insertion of the trunnions in the aper tures 29 without necessity of any additional retaining means.

Turning now to the form of the invention shown in Figs. 7 to 12", asabo-ve stated, th sforn'i of the invent on is identical with that disclosedin Figs. 1 to- 6 save for the construction of the means for applying the gripp'ng or clamping force. Accordin ly, like reference characters have been applied to a l of the elements that are identical with the first form and the description of the first form will, and is intended' to, apply to this form.

The gripp ng force generating means in this form: is in the nature of a cam lever adapted to be pivotally mounted inthe carrier to at the open end thereof for swinging movement in a plane passing through the longitud nal axis of the clamping means to an open or inoperative position" wherein the blocks Hi may be separated for the" insertion or removal of a tube and to an operative or clamp ng position in which the blocks are forced into gripping relation to a tube. The lever is composed of a tubular socket portion Ml and a bifurcated portion. 5!, the bifurcations having considerable with at their ends. The socket portion 45 is intended i-emovab'ly to" receive an actuating bar or rod, for example,- the same bar that is used in rotating the flaring cone-carrying" bolt in a flaring tool. The cam lever is pivotally mounted on a bolt 42 passing through the bifurcations: near one outer corner thereof. In the remaining outer corner but interposed between the: bifurcations is roller 43 rotatably mounted on a rivet M. This roller 43 projects outof' the bifurcations so" as to engage the end block? it? as the lever is swung to operative position, thereby to reduce the frictional resistance to such movement of the lover; The roller as: also is positioned with its axis slightly 7 5 below the axis of the bolt viewed in Fig. 8,

so that the lever in final operative position has an over-center position assuring its remaining in that position during operation on the tube that has been gripped. As best seen in Fig. 8, the tubular portion 63 also strikes the rightmost block 16 when the lever is in operative position, thereby holding the lever in its slightly over-center position.

In order that the clamping force exerted by the lever may be adiusted and, particularly, so that any wear that may take p ace may be taken up, means is provided for adjust ng the lever relative to the carrier l5. To that end, the bifurcations iii are not mounted directly on the bolt 42 but interposed between the bolt and the bifurcations is a sleeve 45. This sleeve has a cylindrical, external surface and is received in truly circular apertures (it formed in the b furcations 4!. The sleeve is, however, provided with a slightly ecc n ric bore 4'! in which the bolt 42 is received. Thus by rotation of the sleeve 45 the lever will be ad usted longitud nally of the carrier l5 because of the eccentricity of the bore in the sleeve. To facilitate ad ustm nt of the sleeve, it is formed with a plura ity of radial recesses 48 intermediate the ends thereof so as to be accessible through the space between the bifurcations. Anv pointed instrument may be nserted into one of the recesses and the sleeve g ven the des red degree of rotation. Thereaf er the bolt 52 which passes loos ly through the leg is of the carrier 15 and is threaded into t e leg !8 o the carrier is rotated to clamp the sl eve ti htly between the two le s. The s e ve ,5 is for this purpose made sli htly longer than the thickness of the lever and has ts ends knurled or serrated, as shown in Fig. 12.

The st ps nvolv d in use of this form of c amping means are generally the same as those involv d in using the first form save that fewer movements on the part of the workman are requir d. Thus, to gr p a piece of tube the workman first swings the l ver to the position shown in F 9. then separates the b ocks at the desired point depending upon the size of the tube to be gripp d, inserts the tube, and then swings the lever toward operat ve or gr pping position endin with t e'l ver in the pos tion shown in Figs. '7 and 8. It w ll be a prec ated that initially the end edge A or" the bifurcations 4! will en age and cam the block H5 into gripp ng engagement w th the tu e. Once the initial g pping of the tube has taken place, the roller 43 engages the end b ock as o apply the final ripping force as the lever moves to its beyond dead center position, shown n Figs. '7 and 8. By this simple movement, the tube is clamped and by an equa ly s mple movement, that of aga n swin ing the lever to the position shown in Fig. 9, the tube is released. A further advantage is that in this form the gripping pressure applied to a tube is the same and does not depend upon the strength or the practice of the workman, as is the case where the degree of tightening of a screw device is dependent upon the strength of the workman, or his zeal or lack of ambition.

I claim as my invention:

1. A tube clamping means for a tube working tool com rising, in comb nation, an elongated carrier with means at one end having a generally semi-cylindrical recess formed therein extending perpendicular to the general plane of said carrier, at least three blocks mounted on said carrier for sliding movement longitudinally thereof, each adjacentside face perpendicular to the general plane of said carrier of each of the intermediate blocks and the inwardly facing side face of the end block also having a generally semicylindrical recess formed therein extending perpendicular to the general plane of said carrier, said adjacent faces of said blocks and of the end means of said carrier having complementary recesses with the recesses in any one block of different size and with one of the largest and one of the smallest recesses in one block and the remaining smallest and one of th next largest in the adjacent block, and means at the remaining end of said carrier operable to provide longitudinal force urging said blocks to tube gripping position.

2. A claim according to claim 1 in which the carrier is U-shaped with a pair of legs each having a bearing aperture near its free end, said legs being resiliently biased inwardly and in the free state converging toward one another, and in which the last named means of claim 1 includes a shaft-like member reduced in diameter at each end to form a trunnion rotatably receivable in the aperture in a leg and a shoulder limiting projection of the trunnion into the aperture whereby said last named means is resiliently held between the legs and the legs are held in parallel relationship.

3. A tube clamping means for a tube working tool comprising, in combination, an elongated U-shaped carrier with a pair of legs each having a bearing aperture near its free end, said legs being resiliently biased inwardly and in the free state converging toward one another, at least four blocks loosely mounted in said carrier for sliding movement longitudinally thereof, each adjacent side face perpendicular to the general plane of said carrier of each of the intermediate blocks and the inwardly facing side face of each end block having a generally semi-cylindrical recess formed therein extending perpendicular to the general plane of said carrier, said adjacent faces of said blocks having complementary recesses with the recesses in any one block of diiferent size, one of the end blocks having one of the largest recesses, the adjacent block having a complementary recess and one of the smallest recesses and the next block having the remaining smallest and one of the next largest recesses, and means closing the open end of said carrier operable to provide longitudinal force ap plied on a line passing through the centers of said recesses urging said blocks to tube gripping position, said means being resiliently held journaled in the bearing apertures in said legs to be swingable to an inoperative position to permit spreading of the blocks for the insertion of a tube and to permit total removal of sa d means, for subsequent removal of said blocks, by spreading of said legs.

4. A tube clamping means for a tube working tool comprising, in combination, an elongated carrier open at one end, not less than five blocks of uniform size mounted on said carrier for slidlng movement longitudinally thereof, each adjacent side face perpendicular to the general plane of said carrier of each of the intermediate blocks and the inwardly facing side face of each end block having a generally semi-cylindrical recess formed therein extending perpendicular to the general plane of said carrier, said adjacent faces of said blocks having complementary recesses with the recesses in any one block of different size, one ofthe end-blocks having one of the largest recesses, the adjacent block having a com plementary recess and one of the smallest recesses and successive intermediate blocks having a complementary recess and alternatively one of the next largest and one of the next smallest recesses, and means closing the open end of said carrier operable to provide longitudinal force applied on a line passing through the centers of said recesses urging said blocks to tube gripping position.

GEORGE FRANCK.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 51,048 Holroyd Nov. 21, 1865 66,908 Sweet July 16, 1867 97,046 Chapman Nov. 23, 1869 101,053 sheafier Mar. 22, 1870 136,399 Wilmot Mar. 4, 1873 Number Number 10 Name Date Tuxworth Apr. 13, 1875 Smart Aug. 5, 1884 Griffin Feb. 6, 1906 Frey Nov. 27, 1906 Fuller Dec. 18, 1906 Herrick Aug. 27, 1907 Wile Jan. 13, 1914 Miller Mar. 25, 1924 Butt Apr. 5, 1927 Andrews May 8, 1928 Russell Dec. 9, 1930 Whalan et a1 Mar. 19, 1935 Wilson Dec. 10, 1935 Neukirch Mar. 24, 1942 McIntosh May 30, 1944 Obecny Feb. 11, 1947 FOREIGN PATENTS Country Date Great Britain Nov. 19, 1879 France Nov. 25, 1920 

